Parks of the Pleistocene: Recreating the Cerrado and the Pantanal with Megafauna

Parks of the Pleistocene: recreating the Cerrado and the Pantanal with megafauna in the archeological record) and the extinction of great Parks of the Pleistocene: birds and mammals the world over. An important fact to observe is that, although the climatic changes at recreating the Cerrado the end of Pleistocene happened at the same time all over the world, the extinction of the megafauna began and the Pantanal with 40,000 years ago in Africa and Australia, 12,000 years megafauna1 ago in America, and less than 1,000 years ago in Madagascar and New Zealand (Martin, 1995, Flannery, Mauro Galetti, PhD2,3 Phenology and Seed Dispersion 1995). Group, Department of Ecology (UNESP-Rio Claro) However, other researchers suggest that climate changes alone could have exterminated the megafauna In the past few years, several (ex. Cartelle, 1999; Ficcarelli et al, 2003). With the researchers have proposed increase of rain and temperature, the open savannas the introduction of large would have been reduced in size, detrimentally affecting predators and herbivores to facilitate the reconstruction the expansion of closed humid forests, causing the of natural ecosystems. The introduction of wolves, elimination of the megafauna due to a lack of favorable bears, pumas and even nonnative species such as environment. These researchers don’t accept the elephants and camels, has been suggested by hypothesis that primitive man caused the extinction of researchers to reestablish the ecological balance in the megafauna, alleging that there isn’t a correlation several North American ecosystems, from forests to with megafauna bones. However, areas with a human- deserts (Martin & Burney, 2000). Even the well- megafauna interaction, though not abundant, exist, equipped North American national parks failed to although this evidence is discredited (see Fiedel & protect the entire diversity of great mammals such as Haynes, 2004). Beyond this, in many places the bears, coyotes and wolves (Newmark, 1987). megafauna is not restricted to open spaces; elephants, Predators at the top of the food chain are considered rhinoceroses and other ungulates can be found in to be “keys” to the maintenance of the ecosystem, closed forests. because they regulate the population of the herbivores. It is most probable that both hunting and climatic Without these predators, there is a disproportionate changes played important roles in the extinction of the increase in the populations of herbivores and South American megafauna. Owen-Smith (1992) mesopredators (foxes, raccoons, and squirrels), which proposes that the extinction of the Pleistocene overtax the population of plants and small animals which megafauna involved climatic factors as much as are their foods (Terborgh, 1992; Crooks & Soulé, anthropic ones. Widespread hunting by the Paleo- 1999). Indians would have caused an accentuated decline in Many years before the arrival of the first humans to the megaherbivore population (as happens today in America, the North American savannas held at least several indigenous reservations and protected areas 41 species of great mammals, including wild horses, with a great deal of hunting). The changes in the bisons, camels, giant armadillos, mammoths and giant climate, however, would have fragmented and restricted sloths (Anderson, 1995), while in South America that the distribution of those megaherbivores to places of diversity was much larger (Cartelle, 1999; Fariña et al., low nutritional value, leaving them more vulnerable to 1998). local extinction as much to human, as to stochastic factors. These mega-mammals played an extremely important role in the structure of vegetation communities and In addition to this, extinct mammals possess low the effects of their premature extinction are still poorly reproductive rates, except for nocturnal or arboreal understood (Janzen & Martin, 1982; Janzen, 1986). species (Johnson, 2002). The mammals and birds Some researchers suggest that there is sufficient dependent on the megafauna (such as sabre-tooth evidence to demonstrate that primitive man played a tigers and condors) would have been wiped out as a primary role in the extinction of mammoths, giant sloths, result of the extinction of their prey. camels, llamas, glyptodonts, horses and other species Actually, we still know little about what factors of large mammals, called “megafauna” (Martin, 1995; caused the extinction of the megafauna, but, perhaps Haynes, 2001). A strong correlation exists between the most pertinent question is what are the colonization and growth of human populations (visible effects of the extinction of the megafauna on neotropic savanna ecosystems. 1 Sent originally in Portuguese 2 [email protected] With the rapid elimination of South American megafauna 3This work relied upon the support of Carina Denny, Paulo Guimarães Jr, Richard Fariña and Fábio Olmos and is dedicated to Megafauna Team. Mauro Galetti (some authors suggest between eight and three receives CNPq scholarship funding and support from FAPESP and IFS. thousand years ago – De Vivo & Carmignotto, 2004), Natureza & Conservação . vol 2 . n1 . april 2004 - pp. 93-100 95 Point of View Mauro Galetti the absence of large herbivores increased the Based upon what we know about South American dominance of some plants, resulting in an accumulation fossils, and knowing the ecological role of the of dry vegetation biomass susceptible to fire. With the megaherbivores in Asia and Africa, certainly all the extinction of easy and naïve prey, such as the large ecosystems, which we know today, particularly the megaherbivores, primitive man intensified the use of Cerrado and the Pantanal, are the result of a massive fire to facilitate the hunting of other mammals, initiating defaunation of great mammals and environments highly the alteration of the savanas (or, that is, the Cerrado) altered by primitive man. as we know them today. It is well known that all of the groups indigenous to the savannas use fire to hunt What does the extinction of the megafauna thousands deer and giant anteaters (Prada, 2001). This type of of years ago have to do with the conservation of today’s hunting has such an impact that some species of large savanna ecosystems, like the Cerrado and the Panta- mammals are already extinct in indigenous reserves nal? The rapid removal of a diverse and abundant (Leeuwenberg, 1997). megafauna, responsible for a good deal of the wealth of species and certainly for most of the vertebrate My generation grew up greatly influenced by “Animal biomass of those ecosystems, is reflected until today Planet” and other nature programs, all, almost without in the ecological processes of the neotropic savannas. exception, about African savannas. I grew up thinking A comparison between the Emas National Park (Par- Africa was the continent of mammals, while South que Nacional de Emas) in Goiás state with the Kruger America was the continent of birds. The great African National Park in South Africa, or with other African parks, like Serengeti, Okavango, Ngorongoro and parks, can elucidate and open up new horizons in our Kruger, with their herds of zebras, elephants, gnus understanding of our ecosystems. and so many other mammals, were the image of wild nature. Emas National Park is a savanna, 132 Thousand hec- tares (326 acres) in size, which has a significant diversity Large mammals have always attracted, and still attract, of large mammals including the pampas deer, the tapir, the interest of most people. One proof of this is the and the jaguar (Silveira et al., 1999). Emas is considered large number of people that visit the elephant or to be the “Brazilian Serengeti” due to its similarity to rhinoceros enclosures at zoos, compared to the the African park. numbers that visit the manned wolves or the capybaras. South American biologists have always Any visitor will observe small groups of pampas deer been slightly jealous of African biologists, because of (Ozotocerus bezoarticus) feeding on the vegetation the lack of large animals in the Neotropics. Few people (Rodrigues, 2003). It is estimated that the park shelters are aware, however, that the population of large South about 1,300 pampas deer, that is, a biomass of 35 kg/ American mammals was, at one point, much richer than km2 (199 lbs/sq. mi.) (Rodrigues, 2003). If we include that found today in Africa. tapirs, white-lipped peccary, red brockett deer and brown brockett deer, the biomass of “large” mammals If we could go back in time at least ten thousand years, doesn’t exceed 100 kg/km2 (570 lbs./sq. mi.) (F. H. G. to the end of the Pleistocene, the savannas of South Rodrigues, pers. comm.). In the African parks, on the America (such as the Cerrado and the Pantanal) were other hand, the biomass of large herbivores can vary more spectacular than the savannas of Africa. Whereas from 5,000 to 22,500 kg/km2 (28,500 to 128,250 lbs./ in Africa there exist only five mammals of more than a sq. mi.), where gnus, zebras, elephants, rhinoceroses, ton (elephant, two species of rhinoceroses, hippo- impalas and other mammals are easily seen (Caro, potamus and the male giraffe), in South America during 1999). the Pleistocene there were more than 38 genera above 100 kilos (220 lbs.), and from ten to twelve species In the Pantanal, known as the place with the largest above a ton, in one single place (Fariña et al., 1998). abundance of mammals in the neotropics, the biomass of the wild herbivores (like pampas deer, deer and Herds of horses (Equus and Hippidion), giant sloths capybaras) doesn’t exceed 1,000 kg/km2 (5,700 lbs./ weighing up to five tons (Eremotherium), mastodon, sq. mi.) (Tomás et al., 2001; Mauro et al., 1998; Galetti which were similar to four ton elephants (Stegomastodon et al., data not published), while the biomass of and Haplomastodon), Xenorhynoterium, which looked nonnative animals, like cattle, feral hogs and buffaloes like one ton camels, the Toxodon, similar in size and can reach more than 5,000 kg/km2 (28,500 lbs./sq.

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